Hey Napjohn8,
I'm from Mississauga as well but haven't really mastered the area I've been living in my whole life. It wasn't until the last couple of years or so I started to venture about the lakeshore and look for good spots to take a couple of casts.
Like you, I find the most action around here is when the Salmon run in the fall, but you can also find cats in the Credit usually in the 1 to 3 pound range year round.
Of course, come mid-May Pike can be found around the T.O. islands and harbourfront. In June, bass, carp, bowfin and cats are also found.
Anyway, all I can say is keep tryin' and you never know what you might hook into. I take a camera with me just in case I catch that two-headed pike, lol.
Best of luck,
reefrunner